The subject application relates to toner consumption calculation and/or calibration for a printing device that employs multiple interacting color separations. While the systems and methods described herein relate toner calibration, it will be appreciated that the described techniques may find application in other resource cost estimation systems, other xerographic applications, and/or other printing systems.
Classical methods of calculating the amount of toner consumed in an electro-photographic system generally involve some form of calculating the area coverage of each region of the page, and applying a Tone Reproduction Curve (TRC) metric to convert from digital coverage to toner and/or cost. (A TRC is often implemented as a one dimensional lookup table, but it could also be implemented as a functional form). They operate in a separation-independent manner. On many print engines, in which the amount of toner a given separation consumes depends on the amount of toner previously present for prior separations, separation-independent calculations give inaccurate results.
One such technique converts from bit coverage to material consumption in the single separation case. Another addresses using computed materials and converting to costs and/or prices. Yet another uses a reduced resolution image. Several others address using a subset of the pixels to compute the coverage statistically. Another addresses printing and scanning, and then estimating the coverage from the scan, as well as simply calculating the coverage from the bitmap and printing the calculated result on the document. Another technique uses a model of halftone dot growth to predict toner consumption.
For example, U.S. Pat. No. 5,204,699 addresses converting from bit coverage to material consumption in the single separation case. U.S. Pat. No. 5,383,129 addresses taking computed materials and converting to costs and/or prices. U.S. Pat. No. 6,356,359 addresses using a reduced resolution image. U.S. Pat. Nos. 5,604,578 and 5,592,298 relate to taking a subset of image pixels to compute the coverage statistically. U.S. Pat. No. 7,359,088 relates to printing, scanning, and estimating the coverage from the scan, calculating the coverage from the bitmap, and printing the calculated result on the document. US Application 2008/0075480 A1 addresses a model of halftone dot growth to predict toner consumption. However, all of these techniques are susceptible to inaccuracies when dealing with interacting color separations.
Accordingly, there is an unmet need for systems and/or methods that facilitate calculating toner consumption for a printer that uses interacting color separations, while overcoming the aforementioned deficiencies.